Folding machine



F. A. ERICSON FOLDING MACHINE July 2, 1929.

2 Sheets-Sheet Filed Oct. 20, 1926 July 2, 1929. F. A. ERlcsoN FOLDING MACHINE Filed Oct. 20, 1926 @Figa 2 Sheets-Sheet 2 Patented July 2, 1929.

UNITED STATES PATENT OFFICE.

FRITZ A. ERICSON, OF CHICAGO, ILLINOIS, ASSIGNOR T0 UNITED SHOE MACHINERY CORPORATION, OF PATERSON, NEW JERSEY, A CORPORATION 0F NEW JERSEY.

FOLDING MACHINE.

This invention relates to folding machines and is herein illustrated as embodied in a machine particularly designed to fold the round corners of the covers of book cases.

The case of a book commonly comprises a backing, usually in the form of two boards which may be made of materials of different degrees of stiffness, and a cover which is made of flexible material such as cloth, leather or imitation leather. If the finished case is to have round corners, the backing is provided with four round corners of the desired curvature. The cover, which commonly has similarly rounded corners, is some- What larger in outline than the backing so that its margin projects beyond the edges of the backing in position to be folded over the edges, it being understood that the margin of the cover is coated with paste or other cement prior to the folding operation. In folding the cover it is in some instances found desirable to carry out the operation as follows: First the margins of the cover along the straight edges thereof are folded by hand over the backing up to within a short distance of the corners, and then these corner margins are folded by a machine.

In those instances in which the straight portions of the margin of the cover are folded first, there are short stretches of the margin located between the completely folded over portion of the margin and the extreme corner of the margin which are partly folded and overhang more or less the margin of the backing. The mechanism for folding the corner portion con'xmonly comprises a folder and a forming plate cooperating with the folder having an operative edge curved to correspond to the curvature of the corner of the backing; and this forming plate must be moved into position above the backing with its curved edge substantially in register with the edge of the curved corner of the backing before the corner folding operation is started. It is ordinarily impractical to bring the forming plate directly down into the desired position by reason of the fact that the straight portions of the margin adjacent to the corner are partlyy folded so that the plate would descend upon them. It is therefore desirable.

Application filed October 20, 1926. Serial No. 142,990.

to slide the plate into operative position so that it will pass beneath those portions of the straight margins which have been partly folded over.

In view of the foregoing the present invention provides an improved folding machine of the type referred to which is particularly adapted to fold corners of the kind described although, as will be apparent, it may be used to fold the corners before the Straight portions of the margin have been folded.

According to one feature of the invention, the forming plate of the illustrated machine is pivoted to a carrier which is swung toward the work support to bring the plate into a position substantially parallel to the body portion of the work and then to move it along the surface of said ortion into op erative relation to the margin at the corner of the work preparatory to the corner folding operation. In the use of the illustrated machine the work, with the straight portions of the margin of the cover already folded. is placed upon a suitably shaped work sup port and `in contact with suitable edge guides; and then the carrier with the forming plate pivoted to it is swung down. The location of the pivot with respect to the plate is such that the forward end of the plate is normally lower than the rear end. As the carrier swung down, `the forward end of the plate contacts with the work. and then the plate assumes a substantially l1ori zontal position and slides along the surface of the work. And, in order to ensure that the forward end of the plate shall be close to the body of the work so as to more freely beneath the partly folded over portions ot the margin of the work adjacent to the corner, a yielding member mounted in the work support acts through the work to push up on the rear end of the plate and thereby keep the forward end of the plate close to the work. Tith this construction the forming plate is readily moved into operative relation to the unfolded margin of the work at the corner thereof without danger .of displacing any partof the margin which has already been partly folded.

When the margin at a corner of a plece of work is folded to produce a round corner, that margin is necessarily plaited. It is very desirable that such plaits should be small and evenly spaced so that no bunches will result in the finished work. According to another feature of the invention there is provided, in combination with a forming plate which is slid over the body portion of the work into operative relation to a corner portion ot the margin, a forming block around which the corner portion of the margin is gathered by the folder, said block cooperating with the folder during the folding operation. ln the illustrated machine this block has a conveXly curved face and mounted for sliding movement along the surface of the forming plate in the path of movement of the folder, such sliding movement being resisted by a spring. Before the folder acts upon the margin, said margin is in substantially upright position between the folder and the forming block. As the folder moves forward, the margin is first gathered about the forming block and gripped friciionally between the folder and the block; and thereafter, as the folder continues its forward movement, the margin is pulled tightly about the round corner of the backing and the plaits are laid down evenly.

These and other features of the invention including certain details of construction and combinations of parts will be described as embodied in an illustrative machine and pointed out in the appended claims.

Referring now to the accompanying drawings,

Figure 1 is a perspective of a machine in which the present invention is embodied,

Figure 2 is a perspective of the work support and its mounting,

Figure 3 is a vertical longitudinal section through the machine,

Figure 1 is a perspective showing more particularly the means for adjusting the able up and down,

Figures 5, (3 and 7 are details in section, showing the work-engaging parts of the niachine in different positions which they occupy during the operation of the machine, and

Figure S is a perspective of a corner portion of the book case, at the stage of operation indicated in Figure 5.

Referring now more particularly to Figures 1, 3, 5, G and 7, the general mode of operation of the illustrated machine will be brieliy described. The corner portion of the work comprising the boards or backing 100 and the cover 200. in substantially the condition shown in Figure 8, except that the corner of the cover is not upright, is placed upon a work support 9 with the straight edges of the work in contact with the straight guides 11, and the corner portion in contact with the curved guide 13. Power having been applied to the machine, the following operations take place: Two clamps 15, i6 descend upon the work to clamp it to the work support. A forming` plate 17, having;` mounted upon it a forming block 19, is swung downward and to the left until its curved edge, which is appropriately shaped, registers substantially with the curved edge at the corner of the backing 100. This brings the parts of the macnine and the work into the positions shown in Figure 5 in which, it will be noted, the forming block 19 is just behind the inner face of the upstanding corner portion of the margin of the cover, and the Work has been pressed down firmly upon the work support, the corner portion havingr been bent sharply up at right angles to the body portion. Meantime the folder 21, which has an operative edge concavely curved to correspond to the convcxly curved face of the forming block, has moved down into the position shown in Figure 5. The folder now moves to the right to fold the corner portion of the margin of the cover over the edge of the form ing plate. ln doing so, it first gathers the margin about the forming block, as shown in Figure 6, and then moves the forming block with it during the folding operation, as indicated in Figure 7, such movement of the block being resisted by a coiled spring 23. vWhen the parts have reached the positions shown in Figure 7, the forming plate 17 is withdrawn from beneath the folded over margin, and the folder Q1 descends to press the fold, after which the parts return to their normal positions of rest, as shown in Figures 1 and 2.

Then the folder gathers the corner portion of the margin about the forming block. as indicated in Figure G, the puckers formed tend to be evenly spaced. The folder and the forming block maintain a pressure upon these puckers which prevents them from becoming displaced, the margin being dragged between the folder and the block during the folding operation. These two members also grip the margin frictionally and act to pull the cover tightly about the edge of the forming plate.

The general mode of operation of the machine having been outlined above, a detailed description of its construction will now be given.

The work support 9, which is of a generally triangular shape (Fig. 2) and has a rounded corner 24 corresponding to the desired curvature at the corner of the finished work. has a downwardly projecting portion having an undercut slot to receive a guide 25 formed on the upper portion of a slide Q7, said slide having guideways 29 to receive stationary guides 31 carried by the bed 33 of the machine. The upper surface of the slide is inclined, as shown in Fig. 2, to it against the inclined bottom of the downward projection on the work support 9 so that, when the slide is moved in one direction or the other, the work support is raised or lowered. To effect such movement a screw 35, threaded into the slide, has its stem rotatably mounted in but held from longitudinal movement with respect to a lug 37 projecting downwardly from the table The work support 9 has two of its edges substantially in contact with the converging walls of the guides 11 and its rounded corner substantially in contact with the rounded guide 13.

The clamps 15, 16 are substantially alike, and only one of them will be described in detail. The clamp 15 is formed at the outer end of an arm 18 the inner end of which is pivoted at 39 to a post 41 which is carried by the bed 33 of the machine. Midway between its ends the arm carries a roll 43, which is adapted to run on a cam 45 fast to a countershaft 47. A compression spring 49 tends at all times to swing the arm upward and thus to hold the roll against the cam. The clamp 16 is formed at the outer end of an arm 20 which is practically like the arm 18 and mounted in the same inanner. A cam 51, which is identical with the cam 45, serves to actuate the arm 20. The cams 45, 51 are so shaped that, when one revolution is imparted to the shaft 47, the clamps are brought down upon the work to hold it stationary during the operation of the other work-engaging parts, and are then raised into the positions shown.

The forming plate 17 is fast at its rear end to the underside of a carrier 53, said carrier being pivoted at 55 to the lower end of al stem 57, the stem being slidable in a socket formed in the lower end of an arm 59. A compression spring 61 (Fig. 5), located in the socket, bears upon the top of the stem 57; and a pin 63 driven into the stem 57 and extending into a slot in the wall of the socket limits the extent to which the spring is permitted to push the stem down and also prevents the stem from turning in the socket. The arm 59 has at a split hub which is fastened by a pinch screw 65 to a rock-shaft 67 mounted in the arms of a stationary bracket 69. This rock shaft has fast to it at about its middle one end of an arm 71, the outer end of which is connected by a link 73 with the outer end of a cam lever 75. This cam lever (Figure 3) is pivoted at its inner end at 77 to a stationary bracket .79 and carries a roll 81 which runs on a cam 83. said cam being fast to the rock-shaft 67. The rock-shaft 67 is normally held in the position shown in Figure 1 by a spring 85 coiled about the shaft 67 and having one end fast to thehub of the its upper end arm 71 and the other end fast to a collar 87. The collar 87 has a hub (not shown) which projects into a socket in the farther upright of the bracket 69, a set screw 89 being provided which engages the hub of the collar 87 and holds said collar in adjusted angular position. By loosening the set screw and turning the collar 87 the spring 85 may be wound up to the desired degree, after which the set screw may be tightened. It will be noted that this spring 85 holds the roll 81 of the cam lever 75 in contact with the cam 83. This cam is so shaped that, when rotated, it acts tirst to swing the forming plate 17 down into the position shown in Figures 5 and 6, then to hold the plate in this position during the folding operation and finally to permit the torsion spring 85 to withdraw the plate from beneath the folded over margin of the work and return it to initial position. The forming plate 17, it should be noted is so mounted that, when the arm 59 is swung down, the forward curved end of the plate strikes the work tirst. In order to ensure that this forward end of the plate shall be kept in contact with the work during the latter part of its movement to operative position, there is carried in a socket in the work-support 9 a ball 90 resting upon a coiled spring 92 which, in turn, rests upon the upper end of a screw 94. The screw is so adjusted that the ball normally projects above the surface of the work-support. When now, the forming plate 17 is swung down from the position shown in Figures 1 and 3 to that shown in Figures 5, 6 and 7 the ball, acting through the work, presses upwardly upon the under side of the rear portion of the plate 17, thereby tending to tilt the plate about its pivot 55 and to maintain the forward curved end of the plate in contact with the work. The purpose of this construction is to ensure that the operative edge of the plate shall not foul the partly folded over margin of the work near the corner thereof (see Figure 8), but shall pass readily beneath it.

The forming block 19 (Figs. 5 to 7) is fast to one end of a small rod 96 which is slidable in the block 53. A pin 98, which passes through the rod, serves as a stop to limit'the extent to which the spring 23 is permitted to move the rod, and with it the forming block 19, toward the left.

The folder 21 is fast to the outer end of a rod 91 which is slidably mounted in a tubular carrier 93, a coiled spring 95 tending at all times to move the rod, and with it the folder, to the left as viewed in the figures. Carried at the left-hand end of the rod 91 is a roll 97 which is held by the spring 95 against a cam 99 fast to a rotary drive shaft 101. The tubular folder carrier 93 has on its under side a lug 103 having a slot 105 to receive loosely a pivot pin 107 carried by brackets which are rigid with the bed of the machine. Mounted in the upper portion of the tubular folder-carrier 93, near its right-hand end, is a roll 109 which is held against a cam 111 on the shaft 47 by two compression springs 113, 115, said springs resting upon the bed of the machine and bearing with their upper ends against 'the under side of the folder-carrier 93. rl`he cams 111 and 99 are so shaped that, when the shafts 101, 47 are rotated, the folder 21 is first brought down into the position shown in Figure 5, then moved to the right to fold the margin of the work (Figs. 6 and 7) and then moved down a short distance to press the fold.

In order to prevent the accumulation on the under face of the folder of the paste with which the margin of the work is coated, there is located beneath the folder a block 117 having a groove in its upper surface in which is set a piece of felt which is moistened from time to time. As the bottom of the folder moves over this piece of felt, any paste which may be present on the lower face of the folder is wiped off.

The shaft 47 is driven from the shaft 101.

by a chain 119 which passes around a sprocket 121 on the shaft 47 and around av second sprocket (not shown) on the shaft 101. The shaft 101 has fast to it near its middle a large gear 123 to which power may be supplied in any suitable manner. Preferably power will be supplied through a clutch constructed and arranged, upon heilig operated, to impart one revolution to the shaft 101 and bring it to rest in the position shown. Alternatively the shaft 101 may be rotated continuously from a suitable source of power. It is believed to be unnecessary to show either of these constructions since they form no part of the present invention and any suitable and well known construction may be employed.

In the operation of the machine, assuming a treadle-controlled one revolution clutch to be employed, the work is placed upon the work-support 9 and the clutch thrown in. The cams 45 and 83 cause the clamps 15, 16 to descend upon the work and clamp it to the work-support. The forming plate 17 is then swung down upon the work and slid along the surface of the work into the position shown in Figure 5 carrying with it the forming block. At this time the corner portion of the margin of the cover is bent upright against the guide 13 and extends up between the folder 21 and the forming block 19, the curved edge of the plate 17 as well as the curved edge of the forming block being substantially in register with the curved edge of thev corner of the backing 100. The folder meantime has descendedand now moves to the right. In doing so it first gathers the upstanding margin of the cover about the forming block and then pushes the forming block to the right with it during the folding operation. rIhe margin is thus frictionally gripped and pulled tightly about the edge of the backing, the gripping action serving also to prevent from being displaced the puckers which were formed when the margin of the cover was gathered about the forming block. After the parts have reached the position shown in Figure 7, the forming plate is withdrawn from the fold and raised to initial position, and the folder descends to press the fold against the work support, the block 117 yielding during this pressing operation. Thereafter the folder and clamps rise to their initial position and the machine comes to restas shown in Figure 1.

The illustrated machine is similar in many particulars to the machines shown, described, and claimed in applications Serial Nos. 650,557, 729,930 and 81,814, filed respectively, August 9, 1923, August 4, 1924 and January 16, 1926 in the name of Perley R. Glass, and to the machine shown, described, and claimed in application Serial No. 35,111, tiled June 5, 1925 in the name of James E. McIntire; and the subject-matter common to these applications, and to the present application, is not herein claimed.

Although the invention has been set forth as embodied in a particular machine, it should be understood that the invention is not limited in the scope of its application to the particular machine which has been shown and described.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is 1. A corner folding machine having in combination a support for the work, a forming plate, a carrier to which said plate is pivotally connected, means for swinging the carrier toward the support to bring the plate into a position substantially parallel to the body portion of the work and to move it' along the surface of said body portion into operative relation to the margin at the corner of the work, a folder', and means for operating` the folder to fold said margin over the forming plate.

2. A corner folding machine having in combination a support for the work, an arm mounted for swinging movement, a forming plate pivotally and yieldingly carried thereby, means for swinging the arm toward the support to cause the plate to contact with the work, to tilt on its pivot and to move into operative relation to the margin at the corner of the work, a folder, and means for operating the folder to fold said margin over the forming plate.

3. A corner folding machine having in combination a support for the work, an arm mounted for swinging movement, said arm having a socket, a stem slidable in the socket,

a spring in the socket arranged to bear upon the stem` a forming plate pivotally carried by the stem, means for swinging the arm to bring the forn'iing platfA into operative relation to the margin at a corner of the work, and means for folding said margin over the plate and for pressing the fold.

4. A corner folding machine having in combination a support for the work, a forming plate, a carrier on which the plate is pivotally mounted, means for operating the carrier to move the plate over the work intooperative relation to the margin at the corner of the work. means carried by the support for holding the rear end of the plate raised and the forward end in contact with the work during part of the movement of the plate, and means for folding the said margin over the plate.

5. A corner folding machine having in combination a support for the work, a forming plate, a carrier on which the plate is pivotally mounted, means for operating the carrier to move the plate over the work into operative relation to the margin at the Corner of the work, means carried by the support and acting through the work for holding the rear end of the plate raised and the forward end in Contact with the work during part of the movement of the plate, and means for folding the said margin over the plate.

6. A corner folding machine having in combination a support for the work, a forming plate carrier normally located above the support, a forming plate pivoted to the carrier, means for swinging said carrier downward and forward to bring the operative edge of the forming plate close to the corner portion of the margin of the work, means carried by the support for holding the rear end of the forming plate raised during part of its swinging movement to cause its forward end to press down upon the work, and a folder for folding the margin of the work over the forming plate.

7. A corner folding machine having in combination a Work support, a forming plate movable along the surface of the Work into operative position with respect to the margin at the corner of the work, a cooperating forming block located above the plate, and a folder movable over the plate to gather said margin about the forming block and to fold it over said plate.

8. A corner folding machine having in combination a work support, a forming plate movable toward the work and then along the Work into operative position with respect to the margin at the corner of the work, a forming block located above the plate and also movable into operative relation to said margin, and a folder movable over the plate to gather said margin about the forming block and to fold it over said plate.

9. A corner folding machine having in combination a work support, a forming plate movable toward the work and then along thc work into operative position with respect to the margin at the corner of the work, a forming block located above the plate and movable with the forming plate into operative relation to said margin, and a folder movable over the plate to gather said margin about the forming block and to fold it over said plate.

10. A corner folding machine having in combination a work support, a forming plate, a forming block located above and movable with respect to the plate, a common carrier for the plate and block, means for operating the carrier to cause` the forward end of the plate to move into operative relation to the margin at the corner of the work in a path the latter portion of which is substantially parallel to the plane of the body portion of the work, a folder, means for moving the folder over the plate lo gather said margin about the block and fold said margin over the forming plate, means for withdrawing the plate from the fold, and means for pressing the fold.

11. A corner folding machine having in combination a work support, a forming plate, a forming block located above and movable with respect to the plate, a common carrier for the plate and block, means for operating the carrier to cause the forward end of the plate to move into operative relation to the margin at the corner of the work in a path the latter portion of which is substantially parallel to the plane of the body portion of the work, a folder, means for moving the folder over the plate to gather said margin about the block and fold said mlrgin over the forming plate, means for withdrawing the plate from the fold, and means for causing relative movement of approach between the folder and the support to press the fold.

12. A corner folding machine having in combination a work support, a forming plate, means for so moving the plate that its forward end travels along the surface of the body portion of the Work into operative relation to the margin at the corner of the work, a folder, means for operating the folder to fold said margin over the forming plate, and means cooperating wit-h the folder for exerting a drag on the inner face of the margin during the folding operation.

13. A corner folding machine having in combination a work support, a forming plate movable into close proximity to the work and then along the work into operative relation to the margin at a corner of the work, a folder movable over the Work support in a pat-h substantially parallel to the plane of the surface of said support, and a cooperating block located above the plate Cil arranged to engage the inner face of said margin and adapted to be moved during the folding operation in a path Which is also substantially parallel to the Surface of the Support.

14, A corner folding machine having in combination a Work support, a forming plate movable into close proximity to the work and then along the Work into operative relation to the margin at a corner of the work, a folder, a cooperating block, and means for causing the folder and block to exert a frietional grip on Said margin and to fold it over the forming plate.

l5. A corner folding machine having in combination a Work support, a forming plate, means` for moving the plato toward the work Support and then substantially parallel to the work support into operative relation to the margin at a corner of the work, a folder, means for moving the folder in a path to fold said margin over the forming plate, a tool mounted for movement in the plane of the path of movement of the folder, and yielding meane tending to resist movement of the tool whereby the tool and folder are caused yieldingly to grip said margin and to move together in the framey direction.

16. A corner folding machine having in combination a Work support, meane` for clamping the work upon the support. a formingl plate, ay forming block located above the plate, means for moving the plate and the block toward the work and along the Surface of the Work into operative relation to the margin of the worlt at a corner thereof, a folder', and means for eaueing the folder to gather the margin about the block and to fold it over the plate.

17. A corner folding` machine having in combination a work aupport, meansy for clamping the work upon the support, a forming` plate. a forming block located above the. plate, mean@r for moving the plate and the bloei: toward the work and along the `aurface of the work into operative relation to the margin of the work at a eorner thereof, a folder, means for causing thc folder to gather the margin about. the block and to fold it over the plate, and means4 for causing relative movement of approach between the folder and the Work support to presa the fold.

18. A corner folding machine having in combination a support for the Work, an arm mounted for swinging movement, a forming pla-te pivotally carried thereby, means for swinging the arm toward the support to cause the plate to contact with the Work, to tilt on its pivot and to move into operative relation to the margin at the corner of the work, a folder, and means for operating the folder to fold said margin over the forming plate.

19. A machine for operating upon the round corner of a book case, the margin of the cover of which has been partially folded over the margin of a board adjacent to a round corner of the board, Said machine having, in combination, a support for the work, a forming plate the forward edge of which is curved, means for moving the forming plate to cause its forward edge to paas beneath the partially folded margin of the cover into substantial register with the round corner of the board, a forming block located above the plate and movable With respect thereto, and a folder movable over the plate to gather the unfolded portion of the margin of the cover about the block and to fold it over the plate.

20. A machine for operating upon the round corner of a bool( case, the margin of the cover of which hae been partially folded over the margin of a board adjacent to a round corner of the board, said machine having, in combination, a Support for the work, means for clamping the work upon the aupport, a forming plate the forward edge of which is curved, means for moving the forming plate to cause itsr forward edge to pass beneath the partially folded margin of the cover into substantial regiater with the round corner of the board, a forn'ling block located above the plate and movable with respect thereto, and a folder movable over the plate to gather the unfolded portion of the margin of the cover about the block and to fold it over the plate.

In testimony whereof I have Signed my name to this specification.

FRITZ A. ERICSON. 

